Answer:
B. often use tube feet to move around in their environment
Explanation:
Tube feet are tiny tubular projections of echinoderms on the underside (oral side). They are a member of the echinoderm water vascular system.
Tubular feet are used for feeding, breathing and shifting. They are arranged around the sides, in grooves. They work by hydraulic pressure. They are used to transfer food in the centre to the oral mouth, and may stick to surfaces. Tube feet allow certain animals to stick and travel slowly to the ocean floor. for example starfish uses tube feet for the above functions.
Hence, the correct option is B.
Rapid environmental changes can cause:
1) Species can become vulnerable to extinction.
2) A decrease or increase of populations.
3) Diversity of species.
Answer:
The nitrogen bases can only pair in a certain way: A pairing with T and C pairing with G. Due to the base pairing, the DNA strands are complementary to each other, run in opposite directions, and are called antiparallel strands.
Explanation:
Answer:
Used the C1V1 = C2V2 method for calculations
Explanation:
Component Calculation Volume of Stock to be added
FBS: 100*V1 = 10*25 2.5 mL
Glutamine: 200*V1 = 2*25 0.25 mL
Penicillin: 10000V1 = 100*25 0.25 mL
Streptomycin: 10000V1 = 100*25 0.25 mL
NB: C1 = Stock Concentration; V1 = Volume of stock required; C2 = Final concentration required; V2 = Final volume required